I'd really appreciate some help...I have a Delta Monitor 1500 series single handle shower fixture. I need to replace the cartridge but can't figure out how to remove the existing hardware. I've unscrewed the acrylic handle from the side, removed the round plastic front cover and the screw that was under it. I then slid off the the plastic hot/cold temp. dial. Now I'm stuck. Delta told me the chrome sleeve should slide off...if that's correct, then what's holding it on in the first place? The sleeve appears to be in 2 sections - the back half is stationary and the front half is where the handle attaches and rotates left/right to turn the shower on/off. Are they 2 separate chrome sections or all one piece? How do I remove it? Do I need to take the plate off that's attached to the shower wall? Thanks for any help!